Isolation of an SBA lectin-reactive glycoprotein (gp50) and its identification in Schistosoma mansoni larval and adult worm secretions.

A major 50-kDa soybean agglutinin (SBA)-reactive component present in extracts of Schistosoma mansoni eggs was isolated by SBA lectin affinity chromatography. In polyacrylamide gel electrophoresis (PAGE), the SBA-reactive component was seen as a 100-kDa polypeptide band that after reduction and alcylation was substituted by a 50-kDa component. This suggests that it occurs in native form as a dimer. Monoclonal antibodies produced against gp50 reacted with miracidial and cercarial secretions and with adult worm components including tegumental structures suggestive of a secretory function.